As a general proposition, hand gestures are natural, intuitive human communication tools. Human machine interfaces are growing in importance, as machines proliferate and as human-machine interaction becomes more sophisticated. Human-machine interaction protocols have been plagued by significant constraints, have been limited to lower dimensionality (e.g., in comparison to lifelike 3D), and have been rooted in mechanical instruments (e.g., keyboards and mice) that seem antiquated. While touch surfaces and trackpad devices have shown promise, hand gesture interfaces have simply not evolved. Optimizing and integrating hand gestures into 21st-century communication technology creates a significant challenge for system designers, device manufacturers, and engineering specialists alike.